Conventionally, widely known are forming devices that form a cardboard box in a flat state into a box shape. Such a forming device develops the cardboard box in a flat state three-dimensionally, folds flaps, and joints both ends of the flaps thus folded with an adhesive tape or the like, thereby forming the cardboard box into a box shape.
In recent years, there has been developed a technology in which one robot performs not only the forming operation of a cardboard box described above, but also a series of packing operations such as an operation of storing products in the cardboard box thus formed and a sealing operation of the cardboard box in which the products are stored (e.g., Japanese Patent Application Laid-open No. H11-70917).
The robot disclosed in Japanese Patent Application Laid-open No. H11-70917 is a single-arm robot that includes one arm unit. The robot performs an operation of developing a cardboard box three-dimensionally by using a special end effector provided to a tip of the arm unit. The special end effector includes a suction mechanism and a folding mechanism. The suction mechanism sucks a first side surface of the cardboard box in a flat state and a second side surface adjacent to the first side surface. The folding mechanism folds the first side surface of the two side surfaces of the cardboard box sucked by the suction mechanism by an angle of 90 degrees with respect to the second side surface.
As described above, in the conventional technology, a series of packing operations are performed by using one robot, whereby the efficiency in the packing operations is improved. However, it is desirable that the efficiency in the packing operations be further improved.